Injection-molding method

ABSTRACT

The invention concerns a method of producing an article of footwear comprising: providing an upper; providing a mold and opening the mold; inserting the upper into the open mold; closing the mold; and injecting a pressurized molten resin, wherein, after the injecting, there is a gap filled with the resin between a side wall of the mold and an outer surface of at least a first portion of the upper, wherein the gap is essentially zero at a contacting point, wherein the gap increases gradually from the contacting point in at least a first region of the mold.

TECHNICAL FIELD

The present invention relates to an injection-molding method, a mold,and an article of footwear produced of these partly by injectionmolding.

PRIOR ART

Injection molding is frequently used in the production of footwear.Injection molding provides a useful and cost-effective way of providingelements for footwear, for example a sole for a shoe. It is particularlyuseful, that a sole can be directly injection-molded onto a shoe upper.Pressurized, molten resin is injected into a shoe mold, after placing anupper in the mold. In the methods known in the art however, the sharpclosing edge of the mold causes a resulting sharp boundary of thesolidified resin on the shoe upper. Shoes produced by methods known inthe art therefore have a high weight and a bulky appearance and areprimarily used for technical applications, such as safety shoes whereweight and appearance are less of an issue.

Moreover, it is known that certain problems may occur during the moldingprocess.

In an effect known as pinching, some resin is pinched, for example inthe forefoot area, between separate parts of the mold during the moldingprocess. The resulting pinching has an un-attractive visual appearanceand presently needs to be removed manually.

Another common problem with direct injection molding is flashing.Flashing is an undesired spillover of the resin into areas of the upperwhere it is not desired. During injection molding, the resin may creepinto parts of the upper unintentionally, giving the upper a defectiveand unclean look. This may also adversely affect the desiredbreathability of the upper.

EP 2815668 A1 concerns a method for manufacturing a shoe. The methodincludes the steps of: attaching a sock-shaped base member forming aportion of an upper to a last portion of a core, the core including acore print and the last portion; attaching the core to an outer mold;supplying a molten resin to be a reinforcement member and/or a solemember into between the outer mold and the base member; and allowing themolten resin to cure, thereby forming the reinforcement member and/orthe sole member integral with the base member.

U.S. Pat. No. 4,245,406 A concerns a shoe and its method of manufacturein which an upper and preformed rubber outsole are joined by a foamedpolyurethane, injection-molded midsole.

U.S. Pat. No. 5,647,150 A concerns a method of manufacturing footwear.The method includes the steps of positioning a sock portion over a moldelement in which the sock portion comprises a fabric layer and athermoplastic film layer connected to the fabric layer, such that thethermoplastic film layer is positioned between the mold element and thefabric layer, and injection-molding a thermoplastic material to the sockportion positioned over the mold element such that heated thermoplasticmaterial flows through the fabric layer and bonds with the thermoplasticfilm layer and such that the thermoplastic material at least partiallycovers the fabric layer for forming a portion of an item of footwear.

U.S. Pat. No. 7,081,221 B2 concerns an article of textile-soled footwearand method of making, which employ a simple fabrication process andapparatus that allows fabrication of the footwear outer shell via asingle injection-molding step. The article of footwear has a textilelayer at the ground-contacting surface of the outsole, the textile layerbeing moldably and integrally attached, in a common mold, to the moldedoutsole as it is being created during the injection process.

An objective of the underlying the present invention is therefore toprovide an improved method of injection molding, an improved mold, andan improved article of footwear that is of lower weight, and morevisually appealing compared with the prior art.

SUMMARY OF THE INVENTION

This objective is accomplished by the teachings of the independentclaims, in particular by a method of producing an article of footwearcomprising: providing an upper; providing a mold and opening the mold;inserting the upper into the open mold; closing the mold; and injectinga pressurized molten resin, wherein, after the injecting, there is a gapfilled with the resin between a side wall of the mold and an outersurface of at least a first portion of the upper, wherein the gap isessentially zero at a contacting point, wherein the gap increasesgradually from the contacting point in at least a first region of themold.

An article of footwear may be any type of shoe, for example a runningshoe, a golf shoe, tennis shoe etc., or any type of boot, for example afootball boot, a hiking boot, etc. or a sandal etc.

It is to be understood, that the upper may comprise a textile, forexample, the upper may be knitted, woven, or non-woven. The upper maycomprise a synthetic material, leather, natural fibres, etc. Therefore,they may not be a sharp interface between side wall of the mold and anouter surface of the upper. For example, if the upper is knitted, theupper may comprise channels formed by knitting. Hence, the term“essentially zero” is to be understood to be smaller than the variationsin height of the material of the upper.

The resin may be for forming a sole element in addition to serving as acoating applied on the upper, for example to make the upper morewaterproof or abrasion resistant. There may be no need to cut a moldedsole element, therefore further reducing the waste.

Instead of a sharp boundary between an uncoated region of the upper andthe resin, the resin gradually fades. Therefore, the weight of thearticle of footwear is reduced. Moreover, the inventors have found, thatmechanical properties of the article of footwear are improved. Thediscontinuity between the coated and uncoated regions, as known in theart, leads to discontinuities in the stiffness of the article offootwear. This is not only experienced as uncomfortable, but also leadsto a weak spot, at which the upper is likely to break over time.Therefore, the present method improves the durability of the upper.Moreover, the inventors have found, that this gradual fading may reduceor prevent unintended flashing. This also reduces the amount of wastedue to lower rejection rates for finished articles of footwear. Theremay be no need to cut a molded sole element, therefore further reducingthe waste.

The resin may comprise a thermoplastic polymer, for examplethermoplastic polyurethane. Thermoplastic polymers are easy to use in aninjection molding process and are advantageous as they may be weldedtogether. Thermoplastic polyurethane in particular is advantageous as italso provides a good level of grip and allows intricate shapes to beformed, that cannot be formed with certain other materials.

The inventors have found that as the resin cools, its viscosityincreases and the pressure decreases when getting closer to thecontacting point. Therefore, the seal made by the mold at the contactingpoint does not need to be sufficiently strong to withstand the injectionpressure, e.g. at an injection channel.

The gap may increase by less than 1 mm, preferably less than 0.75 mm,more preferably less than 0.5 mm, per mm of a distance from thecontacting point in at least the first region of the mold, wherein thedistance is measured along the outer surface of the upper. In otherwords, if the gap increases by less than 1 mm per mm of the distance, anaverage angle formed by the surface of the coating with the outersurface of the upper is less than 45°, i.e. less than arctan(1 mm/1 mm).The inventors have found that this range allows for an improveddurability of the upper and may be especially effective in reducing orpreventing unintended flashing and unnecessary waste due to lowerrejection rates for finished articles of footwear.

It is to be understood that the distance is measured on the surface ofthe upper, i.e. below any resin coating, if present.

The distance may, for example, be a height determined from thecontacting point towards a bottom region of the upper. A height is notnecessarily along an axis defined by the direction of gravity but,instead, from the contacting point towards a bottom region of the upper.This may be advantageous, for example, if a sole element is integrallyformed with a coating. In this case, the gap increases gradually towardsthe sole element, thus allowing for a particularly stable connection ofthe sole element, the coating, and the upper. Alternatively, thedistance may be in any other orientation, for example from a toe regiontowards a heel region of the upper.

The side wall may contact the outer surface at a contacting point at anangle of less than 45 degrees, preferably less than 30 degrees, morepreferably less than 37 degrees, most preferably less than 27 degrees.This angle may be considered an intersection angle in contrast with theaverage angle defined above. The advantages are similar to thosedescribed above, but the inventors have found that the angle at thecontacting point is particularly important in view of preventingunintended flashing and improving the durability of the upper.

The first region of the mold may be arranged within 5 mm from below thecontacting point. In other words, the average angle as defined above mayrelate to a region close to the contacting point. Therefore, unintendedflashing may be prevented effectively, and the durability of the upperis improved.

The side wall of the mold may have a substantially convex shape. Theside wall may have a texture in order to impart a texture on the resin.Therefore, the side wall may be “substantially convex”, i.e. its generalshape in a two-dimensional cross-section is convex, and its surface maycomprise a modulation in the form of texture. The substantially convexshape is advantageous for creating a gradually-fading coating.

Closing the mold may cause at least a second portion of the upper to becompressed. In other words, at least one linear size of the mold may besmaller than the corresponding linear size of the upper. Therefore, acompression of the upper is effected even prior to the injection of thepressurized molten resin. The inventors have found, that this reducesthe amount of unintended flashing or may avoid unintended flashingaltogether.

The material of the upper may be compressed by a first compressiondistance in a first part of the upper and a second compression distancein a second part of the upper, wherein the first compression distancemay be smaller than the second compression distance. For example, theupper may have a first thickness in the first part. The firstcompression distance is the difference between the uncompressed firstthickness and the compressed first thickness, measured for example inmm. In other words, the pressure applied by the mold onto the upper maybe non-uniform. The inventors have found, that this is an effective wayof preventing unintended pinching. For example, the first compressiondistance may be 0.5 mm and the second compression distance may be 1 mm.

The inventors have found, that during injection molding, the pressuredistribution inside the mold may be non-hydrostatic, that is thepressure is not uniform within the mold. This is especially true,further away from the injection point, where the resin has begun to cooldown. Therefore, the different first and second compression distancealso effect different pressures during the actual molding.

The first part of the upper may be arranged in a heel and/or a toeregion and the second part of the upper may be arranged in a lateraland/or a medial region of the upper. In other words, the pressureapplied by the mold onto the upper may be lower in a heel and/or a toeregion than the pressure applied onto a lateral and/or medial region ofthe upper. Unintended flashing is often a problem in a heel and/or a toeregion of the upper. The inventors have found, that a relatively lowerpressure applied by the mold on a heel and/or a toe region of the upperallows unintended pinching to be prevented.

The mold may comprise at least a first part and a second part, whereinthe first part and the second part are joined in a heel and a toeregion. Geometrically, this arrangement is advantageous since it allowsa great variety of shapes to be molded, for example so-called“undercuts”. However, it may lead to the problem of unintended flashingin a heel and/or toe region of the upper if conventional moldingtechniques are applied. Therefore, the present invention is particularlyadvantageous in this configuration.

Injecting a pressurized molten resin may effect a further compression ofat least a third portion of the upper. In other words, additionalpressure may be applied onto the upper by injecting the pressurizedmolten resin. The inventors have found, that this allows a controllablepenetration of the molten resin into the material of the upper.

The pressurized molten resin may, for example, be injected at a pressureof between 5 and 15 bar, preferably between 8 and 12 bar, for exampleabout 10 bar. These pressures allow a uniform distribution of the resinin the mold.

The further compression of the third portion of the upper may cause thegap to open between an outer surface of the upper and the side wall ofthe mold. In other words, there may be no gap prior to the injection ofthe pressurized molten resin. Therefore, a particularly deep penetrationof the pressurized molten resin into the material of the upper may beachieved, which may allow a preferred stiffness, durability, and levelof waterproofness to be achieved. For example, a portion of the gap maybe 0.4 mm thick.

The upper may be arranged on a shoe last, prior to inserting the upperinto the open mold. This advantageously allows the shape of the upper tobe conformed to the final design stage already during the injectionmolding. Therefore, an additional step, in which the upper is shaped isnot required and the total number of production steps is reduced.Furthermore, the last may act to stabilize the upper against a pressureapplied by the mold and/or the pressurized molten resin.

The mold may further comprise at least a first injection channel forinjecting the pressurized molten resin, wherein the injection channelmay be arranged in a heel region of the mold. The inventors have found,that the pressurized molten resin may cool as it is being injected,therefore increasing its viscosity. This arrangement allows aparticularly uniform distribution of the pressurized molten resin.

The injection channel may be arranged underneath the upper, e.g. in aheel region. The inventors have found, that the pressurized molten resinmay cool as it is being injected, therefore increasing its viscosity.This arrangement allows a particularly uniform distribution of thepressurized molten resin.

The mold may further comprise at least a second injection channel. Themold may comprise any number of injection channels. By providing morethan one injection channel, the pressurized molten resin may bedistributed more uniformly.

The upper may be warp- or weft-knitted. A warp- or weft-knitted upper isparticularly stretchable and therefore comfortable to wear, especiallyfor sports shoes. Warp- and weft-knitting is generally referred to asknitting herein. Moreover, channels may be formed in a warp- orweft-knitted upper allowing the flow of the pressurized molten resin tobe controlled. The relatively open fabric of a knitted upper also allowsa deep penetration of the pressurized molten resin into the knit,therefore allowing a close and durable integration of the knit and theresin. Since knitted uppers may be quite fragile, the present inventionallows the durability and wear resistance of a knitted upper to beimproved significantly. However, generally the upper may be produced byany suitable method, for example the upper may be woven or non-woven.

A wale direction may be arranged substantially perpendicular to alongitudinal direction of the upper in a least a fourth portion of theupper. “Substantially perpendicular” in the present context means at anangle of between 60° and 120°, preferably 70° and 110°. A “waledirection” is understood as a direction along a wale. A “longitudinaldirection” is understood as extending from a toe region to a heel regionof an upper. A channel may be formed between adjacent wales. Therefore,the pressurized molten resin may flow in a controllable manner withinthe channels during the injection molding, allowing a desired amount ofcoating, i.e. preventing unintended flashing.

In some examples, a course direction may be arranged substantiallyperpendicular to a longitudinal direction of the upper in a least afifth portion of the upper. A “course direction” is understood as adirection along a course. A channel may be formed between adjacentwales, arranged substantially perpendicular to the course direction.Therefore, the pressurized molten resin cannot flow easily into thechannel during the injection molding, since the walls on the edges ofthe channel may prevent flow into the channel, reducing the amount ofunintended flashing further.

It is therefore possible to create a fourth portion with a deliberateand controlled amount of coating without any indeliberate flashing, anda fifth portion with little or no flashing.

The method may further comprise at least partially filling at least oneknit-opening in the warp- or weft-knitted upper with the resin. Aknit-opening may, for example, be a channel, a partial hole, a partialaperture, a slit, etc. in the knitted structure of a warp- or weftknitted upper. A partial hole or aperture is knitted by holding someneedles during knitting, while others continue to knit. In other words,partial holes or apertures in knitting can be created by holding certainknitted loops on to the needles, creating tuck stitches. This mayadvantageously add support or abrasion resistance to at least one areaof the upper. For example, the area may be a heel region, a lateralregion, and/or a medial region of the upper, where additional supportmay be required.

The resin may adapt to the knitted structure. For example, a thicknessof the resin coating may be sufficiently thin for the knitted structureto remain visible through the resin coating. This way, the structuralproperties imposed by the knitted structure are largely unperturbed bythe coating, but the coating may nonetheless provide abrasion resistanceand waterproofing.

The resin may form a sole element of the article of footwear. Therefore,it is possible to coat the upper and produce a sole element in a singleinjection molding step. Therefore, the number of production steps isreduced. In other words, there may be a “seamless” transition betweenthe sole and the upper.

The sole element may be essentially the entire sole of the article offootwear. In other words, it may not be necessary to attach additionalelements, such as an additional outsole, to the sole element. Therefore,the production is simplified.

The sole element may be a midsole of the article of footwear. The methodaccording to the present invention allows the pressurized molten resinto produce a foamed midsole, therefore allowing preferable cushioning.Since the bending stiffness against lateral bending increases stronglywith the thickness of the material, such a midsole may also provide agood level of stiffness at a low weight. The midsole may be essentiallythe entire sole of the article of footwear or, alternatively, anadditional outsole may be attached in a further step. For example, anadditional outsole may be attached by means of an adhesive, or bywelding, such as high-frequency welding or infrared welding. Preferably,the additional outsole comprises a same material, for examplethermoplastic polyurethane, as the midsole, in order to effect a strongbond between the midsole and the outsole.

The invention further concerns a mold for producing an article offootwear comprising: a side wall forming a cavity for receiving a shoeupper, wherein the side wall is configured to contact the upper at acontacting point and wherein, after injecting a pressurized molten resininto the mold, there is a gap filled with the resin between a side wallof the mold and an outer surface of the upper, wherein the gap isessentially zero at a contacting point, wherein the gap increasesgradually from the contacting point, in at least a first region of themold; and at least a first injection channel for injecting a pressurizedmolten resin.

A side wall forming a cavity for receiving a shoe upper is to beunderstood that the side wall at least partially defines the shape of acavity for receiving a shoe upper. The shape of the cavity may furtherbe defined by other elements, for example a shoe last on which the upperis arranged may also define part of the shape of the cavity. The cavitymay be considered to be part of the mold.

Instead of a sharp boundary between an uncoated region of the upper andthe resin, the resin gradually fades. The advantages thereof have beendescribed herein.

The gap may increase by less than 1 mm, preferably less than 0.75 mm,more preferably less than 0.5 mm, per mm of a distance from thecontacting point in at least the first region of the mold, wherein thedistance is measured along the outer surface of the upper. In otherwords, if the gap increases by less than 1 mm per mm of the distance, anaverage angle formed by the surface of the coating with the outersurface of the upper is less than 45°, i.e. less than arctan(1 mm/1 mm).The inventors have found that this range allows for an improveddurability of the upper and may be especially effective in reducing orpreventing unintended flashing and unnecessary waste due to lowerrejection rates for finished articles of footwear. It is to beunderstood that the distance is measured on the surface of the upper,i.e. below any resin coating, if present.

The distance may, for example, be a height determined from thecontacting point towards a bottom region of the upper. A height is notnecessarily along an axis defined by the direction of gravity but,instead, from the contacting point towards a bottom region of the upper.This may be advantageous, for example, if a sole element is integrallyformed with a coating. In this case, the gap increases gradually towardsthe sole element, thus allowing for a particularly stable connection ofthe sole element, the coating, and the upper. Alternatively, thedistance may be in any other orientation, for example from a toe regiontowards a heel region of the upper.

The first region of the mold may be arranged at least 2 cm above a floorof the cavity. Above a floor of the cavity is to be understood withrespect to the orientation of the shoe upper, and not necessarily theaxis defined by the direction of gravity. Therefore, the resin may forma sole element that does not need to have the gradually-sloping shape ofthe coating, in a region of 2 cm above the floor of the cavity, and agradually-fading coating as described above. Thus, a sole element andthe coating may be formed in a single process step.

The side wall of the mold may have a substantially convex shape. Theside wall may have a texture in order to impart a texture on the resin.Therefore, the side wall may be “substantially convex”, i.e. its generalshape in a two-dimensional cross-section is convex, and its surface maycomprise a modulation in the form of texture. The substantially convexshape is advantageous for creating a gradually-fading coating.

The mold may comprise at least a first part and a second part and thefirst part and the second part may be joined in a heel and a toe region.Geometrically, this arrangement is advantageous since it allows a greatvariety of shapes to be molded, for example so-called “undercuts”.However, it may lead to the problem of unintended flashing in a heeland/or toe region of the upper if conventional molding techniques areapplied. Therefore, the present invention is particularly advantageousin this configuration.

The injection channel may be arranged in a heel region of the mold. Theinventors have found, that the pressurized molten resin may cool as itis being injected, therefore increasing its viscosity. This arrangementallows a particularly uniform distribution of the pressurized moltenresin.

The injection channel may be arranged underneath the upper, e.g. in aheel region. The inventors have found, that the pressurized molten resinmay cool as it is being injected, therefore increasing its viscosity.This arrangement allows a particularly uniform distribution of thepressurized molten resin.

The mold may further comprise at least a second injection channel. Themold may comprise any number of injection channels. By providing morethan one injection channel, the pressurized molten resin may bedistributed more uniformly.

The invention further concerns an article of footwear, comprising: anupper; an injection-molded region comprising a resin, wherein the resinat least partly coats an outer surface of the upper, wherein the resincoating ceases at a first position, and wherein a thickness of the resincoating increases gradually, in at least a first region of the upper.

Instead of a sharp boundary between an uncoated region of the upper andthe resin, the resin gradually fades. The advantages thereof havealready been described elsewhere herein.

The thickness of the resin coating may increase by less than 1 mm,preferably less than 0.75 mm, more preferably less than 0.5 mm, per mmof a distance from the first position in at least the first region ofthe upper, wherein the distance is measured along the outer surface ofthe upper. In other words, if the thickness of the resin coatingincreases by less than 1 mm per mm of the distance, an average angleformed by the surface of the coating with the outer surface of the upperis less than 45°, i.e. less than arctan(1 mm/1 mm). It should be notedthat the first position may correspond to the contacting point describedherein. The inventors have found that this range allows for an improveddurability of the upper and may be especially effective in reducing orpreventing unintended flashing and unnecessary waste due to lowerrejection rates for finished articles of footwear. It is to beunderstood that the distance is measured on the surface of the upper,i.e. below any resin coating, if present.

The distance may, for example, be a height determined from the firstposition towards a bottom region of the upper. A height is notnecessarily along an axis defined by the direction of gravity but,instead, from the first position towards a bottom region of the upper.This may be advantageous, for example, if a sole element is integrallyformed with a coating. In this case, the gap increases gradually towardsthe sole element, thus allowing for a particularly stable connection ofthe sole element, the coating, and the upper. Alternatively, thedistance may be in any other orientation, for example from a toe regiontowards a heel region of the upper.

The outer surface of the resin coating may form an angle of less than 45degrees with an outer surface of the upper at the first position. Thisangle may be considered an intersection angle in contrast with theaverage angle defined above. The advantages are similar to thosedescribed above, but the inventors have found that the angle at thefirst position is particularly important in view of preventingunintended flashing and improving the durability of the upper.

The first region of the upper may be arranged less than 5 mm below thefirst position. In other words, the average angle as defined above mayrelate to a region close to the first position. Therefore, unintendedflashing may be prevented effectively and the durability of the upper isimproved.

The upper may be warp- or weft-knitted. The advantages of a knittedupper have already been described herein.

A wale direction may be arranged substantially perpendicular to alongitudinal direction of the upper in a least a fourth portion of theupper. The advantages thereof have been described herein.

In some examples, a course direction may be arranged substantiallyperpendicular to a longitudinal direction of the upper in a least afifth portion of the upper. The advantages thereof have been describedherein.

The resin may form a sole element of the article of footwear. Therefore,it is possible to coat the upper and produce a sole element in a singleinjection molding step. Therefore, the number of production steps isreduced.

At least one knit-opening in the warp- or weft-knitted upper may be atleast partially filled with the resin. A knit-opening may, for example,be a channel, a partial hole, a slit, etc. in the knitted structure of awarp- or weft knitted upper. This may advantageously add support orabrasion resistance to at least one area of the upper. For example, thearea may be a heel region, a lateral region, and/or a medial region ofthe upper, where additional support may be required.

The resin may adapt to the knitted structure. For example, a thicknessof the resin coating may be sufficiently thin for the knitted structureto remain visible through the resin coating. This way, the structuralproperties imposed by the knitted structure are largely unperturbed bythe coating, but the coating may nonetheless provide abrasion resistanceand waterproofing.

The sole element may be essentially the entire sole of the article offootwear. In other words, it may not be necessary to attach additionalelements, such as an additional outsole, to the sole element. Therefore,the production is simplified.

The sole element may be a midsole of the article of footwear. Theadvantages thereof have already been described herein.

The injection-molded region may be devoid of any pinching. Pinching isan unintended effect that leads to a worse visual appearance. Thearticle of footwear according to the present invention is thereforepreferably devoid of any pinching.

An edge of the coating may be essentially flush with the outer surfaceof the upper. “Essentially flush” means, in this context, within a rangeof fluctuations in height of the outer surface of the upper, which ismay be less than 5 mm, preferably less than 2 mm, most preferably lessthan 1 mm. In other words, “essentially flush” means a “smooth” or“even” transition of the resin into the upper with essentially no hardedges. This way, the transition between the uncoated and coated regionsof the upper is particularly smooth. As explained herein, this isadvantageous as it improves the durability of the upper and reduces orprevents unintended flashing.

It is to be understood that the first, second, third, fourth, fifthportion of the upper may pairwise overlap at least partially, orentirely, or not at all.

SHORT DESCRIPTION OF THE FIGURES

In the following, exemplary embodiments of the invention are describedwith reference to the figures.

FIG. 1 shows an exemplary article of footwear according to the presentinvention;

FIGS. 2A-E shows an exemplary article of footwear according to thepresent invention;

FIG. 3 shows another exemplary article of footwear according to thepresent invention;

FIG. 4 shows another exemplary article of footwear according to thepresent invention;

FIG. 5 shows another exemplary article of footwear according to thepresent invention;

FIGS. 6A-D show exemplary molds and illustrate methods for operationthereof;

FIGS. 7A-B illustrate pinching and flashing in a conventional shoe;

FIG. 8 shows another exemplary article of footwear according to thepresent invention;

FIG. 9 shows another exemplary article of footwear according to thepresent invention;

FIG. 10 shows another exemplary article of footwear according to thepresent invention; and

FIG. 11 shows another exemplary article of footwear according to thepresent invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In the following some embodiments of the invention are described indetail. It is to be understood that these exemplary embodiments can bemodified in a number of ways and combined with each other whenevercompatible and that certain features may be omitted in so far as theyappear dispensable.

FIG. 1 shows an exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises: an upper 11; aninjection-molded region comprising a resin, wherein the resin at leastpartly coats an outer surface of the upper 11, wherein the resin coating12 ceases at a first position, and wherein a thickness of the resincoating 12 increases gradually in at least a first region of the upper11. The resin is for forming a sole element 13 and additionally acts asa coating 12 applied on the upper 11. The article of footwear 10 furthercomprises a tongue 15 and shoe laces. In this example the article offootwear 10 is a running shoe.

The thickness of the resin coating 12 increases by less than 1 mm per mmof a distance from the first position 20 in at least the first region 19of the upper 11, wherein the distance is measured along the outersurface 17 of the upper 11. The distance is a height determined from thefirst position 20 towards a bottom region of the upper 11.

In this example, the upper 11 is weft-knitted. The upper 11 shown inFIG. 1 may be produced by any method disclosed herein using a mold 21 asdisclosed herein.

FIGS. 2A-E show a schematic of an article of footwear 10 according tothe present invention. FIG. 2A shows a lateral view, while FIGS. 2B-Eshow a cross-sectional view through the sections indicated with E-E,D-D, C-C, and B-B, respectively, in FIG. 2A.

The article of footwear 10 comprises: an upper 11; an injection-moldedregion comprising a resin, wherein the resin at least partly coats anouter surface 17 of the upper 11, wherein the resin coating 12 ceases ata first position, and wherein a thickness of the resin coating 12increases gradually along a height, in at least a first region 19 of theupper 11, wherein the height is measured from the first position 20towards a bottom region of the upper 11 along the outer surface 17 ofthe upper 11. The height is measured on the surface 17 of the upper 11,i.e. below any resin coating 12, if present.

The resin forms a sole element 13 of the article of footwear 10. Theinjection-molded region, which comprises the coating 12 and the soleelement 13 is devoid of any pinching. The sole element 13 is a midsoleof the article of footwear 10 and an additional outsole 16 is attachedby infrared welding.

A first exemplary first region 19 a is shown in the cross-sectional cutfrom E-E shown in FIG. 2B. The thickness of the resin coating 12increases approximately symmetrically on both sides by about 0.6 mm permm of height, an average angle formed by the surface 18 of the coating12 with the outer surface 17 of the upper 11 is therefore about 31°,i.e. the arctan(0.6 mm/1 mm).

The outer surface 18 of the resin coating 12 forms an angle of about 35°with an outer surface 17 of the upper 11 at a first exemplary firstposition 20 a.

A second exemplary first region 19 b is shown in the cross-sectional cutfrom D-D shown in FIG. 2C. The thickness of the resin coating 12increases approximately symmetrically on both sides by about 0.4 mm permm of height, an average angle formed by the surface 18 of the coating12 with the outer surface 17 of the upper 11 is therefore about 22°,i.e. the arctan(0.4 mm/1 mm). However, in this cut, the coating 12extends significantly higher on a left side than on a right side of theexemplary upper 11.

The outer surface 18 of the resin coating 12 forms an angle of about 30°with an outer surface 17 of the upper 11 at a second exemplary firstposition 20 b.

A third exemplary first region 19 c is shown in the cross-sectional cutfrom C-C shown in FIG. 2D. The thickness of the resin coating 12increases on a left side by about 0.9 mm per mm of height and on a rightside by about 0.6 mm per mm of height, an average angle formed by thesurface 18 of the coating 12 with the outer surface 17 of the upper 11is therefore about 42° on a left side, i.e. the arctan(0.9 mm/1 mm) andabout 31° on a right side. In this cut, the coating 12 extends toapproximately the same level on a left side as on a right side of theexemplary upper 11.

The outer surface 18 of the resin coating 12 forms an angle of about50°, i.e. more than 45°, with an outer surface 17 of the upper 11 at athird exemplary first position 20 c on a left side and about 40° in aright side.

In the exemplary cuts shown in FIGS. 2B-D, the first region 19 a-c ofthe upper 11 extends to 10 mm below the first position.

A fourth exemplary first region 19 d is shown in the cross-sectional cutfrom D-D shown in FIG. 2C. The thickness of the resin coating 12increases approximately symmetrically on both sides by about 0.35 mm permm of height, an average angle formed by the surface 18 of the coating12 with the outer surface 17 of the upper 11 is therefore about 19°,i.e. the arctan(0.35 mm/1 mm). However, in this cut, the coating 12extends significantly higher on a left side than on a right side of theexemplary upper 11.

The outer surface 18 of the resin coating 12 forms an angle of about 19°with an outer surface 17 of the upper 11 at a fourth exemplary firstposition 20 d.

A smaller angle may be preferred to generate a unique look mimicking afused single-piece shoe where the upper and midsole are indistinctive.In combination with the upper this effect can be enhanced as the uppercould have a specific topography allowing the PU to flash up in someparts (thinner upper) or restrict the PU flow in other parts. The uniquelook could then be reinforced with different upper types or/and zoningsof a customized knit structure.

In the exemplary cut shown in FIG. 2E, the first region 19 d of theupper 11 extends from the fourth exemplary first position 20 d to 4 mmbelow the first position.

The upper 11 shown in FIGS. 2A-E may be produced by any method disclosedherein using a mold 21 as disclosed herein.

FIG. 3 shows another exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises an upper 11; aninjection-molded region comprising a resin, wherein the resin at leastpartly coats an outer surface of the upper 11, wherein the resin coating12 ceases at a first position 20, and wherein a thickness of the resincoating 12 increases gradually, in at least a first region of the upper11. The resin is for forming a sole element 13 and additionally acts asa coating 12 applied on the upper 11.

In this example, a thickness of the resin coating 12 increases graduallyalso along a lateral direction 40 at least in a toe region of the upper.In addition, a thickness of the resin coating 12 increases graduallyalong a height in the toe region of the upper and a lateral region ofthe shoe upper, beginning just behind the toe region.

As can be seen from FIG. 3, the injection-molded region, comprising theresin coating 12 and the sole element 13 is devoid of any pinching.

The exemplary upper 11 is weft knitted. In this example, a waledirection 30 is arranged substantially perpendicular to a longitudinaldirection of the upper 11 in a least a fourth portion 37 of the upper11. A channel 14 a is formed between adjacent wales in the fourthportion 37. Therefore, the pressurized molten resin may flow in acontrollable manner in the fourth portion 37 within the channel 14 aduring the injection molding, allowing a desired amount of flashingfurther, i.e. preventing unintended flashing.

Additionally, a course direction 29 is arranged substantiallyperpendicular to a longitudinal direction of the upper 11 in a least afifth portion 38 of the upper 11. A channel 14 b is formed betweenadjacent wales, arranged substantially perpendicular to the coursedirection, in the fifth portion 38. Therefore, the pressurized moltenresin cannot flow easily into the channel 14 b during the injectionmolding, since the walls on the edges of the channel 14 b may preventflow into the channel, reducing the amount of unintended flashingfurther.

It is therefore possible to create a fourth portion 37 with deliberate,controlled amount of coating but not indeliberate flashing and a fifthportion 38 with little or no flashing. In this example, the fourthportion is located in a toe region while the fifth portion is located ina lateral region of the shoe upper, beginning just behind the toeregion.

FIG. 4 shows another exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises an upper 11; aninjection-molded region comprising a resin, wherein the resin at leastpartly coats an outer surface of the upper 11, wherein the resin coating12 ceases at a first position 20, and wherein a thickness of the resincoating 12 increases gradually, in at least a first region of the upper11. The resin is for forming a sole element 13 and additionally acts asa coating 12 applied on the upper 11.

The exemplary upper 11 is weft knitted. A course direction 29 isarranged substantially perpendicular to a longitudinal direction of theupper 11 in a least a fifth portion 38 of the upper 11. Therefore, awale direction 30 is arranged substantially parallel, i.e. between 0 to30°, to a longitudinal direction of the upper 11 in a least the fifthportion 38 of the upper 11. A channel 14 b is formed between adjacentwales, arranged substantially perpendicular to the course direction, inthe fifth portion 38. Therefore, the pressurized molten resin cannotflow easily into the channel 14 b during the injection molding, sincethe walls on the edges of the channel 14 b may prevent flow into thechannel, reducing the amount of unintended flashing further. However, ascan be seen from FIG. 4, the amount of coating can still be controlledand a coating 12 a may, for example, form a pocket. In this example, thefifth portion 38 is arranged in a lateral region of the upper just aheadof a heel region.

FIG. 5 shows a schematic of another exemplary article of footwear 10according to the present invention. The article of footwear 10 comprisesan upper 11; an injection-molded region comprising a resin, wherein theresin at least partly coats an outer surface of the upper 11, whereinthe resin coating ceases at a first position, and wherein a thickness ofthe resin coating increases gradually, in at least a first region of theupper 11. The resin is for forming a sole element 13 and additionallyacts as a coating applied on the upper 11.

The exemplary upper 11 is weft knitted. Knitted loops are indicated withreference sign 28. A wale direction 30 is arranged substantiallyperpendicular to a longitudinal direction of the upper 11 in a least afourth portion 37 of the upper 11. A channel 14 is formed betweenadjacent wales in the fourth portion 37. Therefore, the pressurizedmolten resin may flow in a controllable manner in the fourth portion 37within the channel 14 during the injection molding. This is illustratedby the vertical arrows.

FIG. 6A shows a cross-section of a mold 21 according to the presentinvention comprising: a side wall 25 forming a cavity for receiving ashoe upper 11, wherein the side wall 25 is configured to contact theupper 11 at a contacting point 24 and wherein, after injecting apressurized molten resin into the mold 21, there is a gap 22 filled withthe resin between a side wall 25 of the mold 21 and an outer surface 17of the upper 11, wherein the gap 22 is essentially zero at a contactingpoint 24, wherein the gap 22 increases gradually from the contactingpoint 24, in at least a first region 39 of the mold 21; and at least afirst injection channel 23 for injecting a pressurized molten resin.

Another way of describing the shape of the mold 21 according to thepresent invention is to say that a bite line of the mold is not a narrowsharp line, unlike in conventional molds, but instead, the bite line isrelatively flat and gradually sloping.

An upper 11 is arranged on a last (not shown separately) and placedinside the mold 21. The cavity comprises both the gap 22 and the upper11 arranged on a last.

The gap 22 increases by less than 1 mm per mm of a distance from thecontacting point 24 in at least the first region of the mold 21, whereinthe distance is measured along the outer surface of the upper 11. Thedistance is a height determined from the contacting point 24 towards abottom region of the upper 11.

The first region 39 of the mold 21 is arranged at least 2 cm above afloor 26 of the cavity, with respect to the orientation of the shoeupper 11.

In this example, the side wall 25 of the mold 21 has a substantiallyconvex shape. The side wall 25 may have a texture in order to impart atexture on the resin, although in this case, the side wall 25 does notcomprise a texture. The mold 21 comprises a first part 27 a and a secondpart 27 b and the first part 27 a and the second part 27 b are joined ina heel and a toe region.

The first injection channel 23 is arranged in a heel region of the mold21. The first injection channel 23 is arranged underneath the upper 11,in a heel region.

The mold 21 may further comprise at least a second injection channel,although in this example, there is only a single injection channel 23.

The resin may be produced by the reaction of one or more compositions inthe mold. For example, the resin may comprise a polyurethane and beproduced by injecting a polyol into the mold at a temperature of about35° C. and further injecting an isocyanate into the mold at atemperature of about 50° C. The polyol and isocyanate undergo anexothermic reaction forming polyurethane and may raise the temperatureof the mold, for example to about 60° C. In this case, foaming of thepolyol and the isocyanate may be the main source of pressure around thecontacting point 24, where the pressure due to the injection pressure ofthe polyol and the isocyanate may be negligibly small.

FIG. 6B in contrast shows a cross-section of a mold 31 as known in theart. A difference between a mold 31 as known in the art and a mold 21according to the present invention is that at a contacting point 34, thegap 22 does not increase gradually from the contacting point 34.Instead, the contacting point 34 defines a sharp boundary with thedisadvantages described herein.

FIG. 6C shows how a mold 21 as shown in FIG. 6A may be opened. The mold21 may be opened by moving the first part 27 a and the second part 27 bin opposite directions along a left 36 a and a right 36 b sidewaysdirection. Geometrically, this arrangement is advantageous since itallows a great variety of shapes to be molded, for example so-called“undercuts” 35, which would not be possible for some alternative moldlayouts, e.g. a mold where a top and a bottom portion are moved relativeto each other to open the mold, as the mold will get stuck while beingopened on an area of the sole element that is projecting outwards. Anundercut may, for example, be part of a ground-engaging profile of ashoe and may improve the grip of a sole.

FIG. 6D illustrates an aspect of a method according to the presentinvention. FIG. 6D shows a cross-sectional outline of an upper, arrangedon a last 43. The last 43 is in tight contact with an inner surface ofthe upper. According to this exemplary aspect, closing the mold causesthe upper to be compressed. In other words, the mold is smaller than thelasted upper. The solid line 41 indicates an outer surface of the upperwhen the upper is not compressed. The dotted line 42 indicates the outersurface of the upper, when the upper is compressed by the mold, prior toinjection of the resin. Therefore, the dotted line 42 indicatesessentially also the side wall of the mold for this cross-sectional cut.An uncompressed thickness of the upper is the distance between thesurface of the last 43, since the upper is tightly arranged on the last43, and the outer surface 41 of the uncompressed upper. A compressedthickness of the upper is the distance between the surface of the last43 and the outer surface 42 of the compressed upper.

The compression distance is the distance between the uncompressed outersurface and the compressed outer surface of the upper, since the innersurface of the upper is arranged tightly on an essentiallyincompressible last 43. The material of the upper is compressed by afirst compression distance 48 in a first part 44 of the upper and asecond compression distance 49 in a second part 46 of the upper, whereinthe first compression distance 48 is smaller than the second compressiondistance 49.

The first part 44 of the upper is arranged in a toe region 44. A similarcompression is effected in a heel region 45. The second part 46 of theupper is arranged in a medial region 46. The upper is compressed by athird compression distance in a lateral region 47 of the upper, whereinthe third compression distance is greater than the first compressiondistance 48 but smaller than the second compression distance 49. In thisexample, the first compression distance 48 is 0.3 mm, the secondcompression distance 49 is 1 mm and the third compression distance is0.5 mm.

FIG. 7A shows an exemplary shoe 50 comprising an upper 51 as known inthe art. The shoe 50 further comprises a sole. The sole 53 is injectionmolded and displays a pinching effect 52 wherein some resin is pinched,in this example in the forefoot area, between separate parts of the moldduring the molding process. The resulting pinching has an un-attractivevisual appearance and presently needs to be removed manually.

FIG. 7B shows another view of the exemplary shoe 50 of FIG. 7A. Theupper 51 displays a flashing effect 54, which is an undesired spilloverof the resin into areas of the upper where it is not desired. Duringinjection molding, the resin crept into parts of the upper 51unintentionally, giving the upper a defective and unclean look.

FIG. 8 shows another exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises an upper 11,which is weft-knitted and coated by a coating 12 comprising a resin by amethod according to the present invention. A plurality of channels 14 isformed in the knitted structure, of which an exemplary two channels areindicated with reference numeral 14. The channels 14 are one example ofa knit-opening 61 which is at least partially filled by resin. Theexemplary article of footwear 10 also comprises a sole element 13,comprising a rear part 13 b and a front part 13 a, wherein the frontpart 13 a is formed by the resin, i.e. the resin comprised in thecoating 12.

FIG. 9 shows another exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises an upper 11,which is also weft-knitted and coated by a coating 12 comprising a resinby a method according to the present invention. A plurality of channels14 is formed in the knitted structure in-between strongly pronouncedribs 62. An exemplary two channels are indicated with reference numeral14 and an exemplary two ribs are indicated with reference numeral 62.The channels 14 are one example of a knit-opening 61 which is at leastpartially filled by resin. FIG. 9 shows an example of how the resin mayadapt to the knitted structure. Part of the ribs 63 is also coated bythe resin. However, the structure of the coated ribs 63 is still visiblethrough the coating 12. A thickness of the resin coating is sufficientlythin for the knitted structure of the ribs 63 to remain visible throughthe resin coating.

FIG. 10 shows another exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises an upper 11,which is weft-knitted and coated by a coating 12 comprising a resin by amethod according to the present invention. A plurality of knit-openings61 is formed in the knitted structure. The knit-openings 61 are partialholes. Some knit-openings 64 are coated by the resin. The resin thustakes a pattern of the knitted upper 11, i.e. visually replicating thetexture of the knitted upper 11. The exemplary article of footwear 10also comprises a sole element 13, comprising the resin.

FIG. 11 shows another exemplary article of footwear 10 according to thepresent invention. The article of footwear 10 comprises an upper 11,which is weft-knitted and coated by a coating 12 comprising a resin by amethod according to the present invention. An edge 65 of the coating isessentially flush with an outer surface of the upper. The exemplaryarticle of footwear 10 also comprises an outsole 16, which is not formedwith the resin but instead attached in a separate step.

Some embodiments described herein relate to method of producing anarticle of footwear comprising providing an upper; providing a mold andopening the mold; inserting the upper into the open mold; closing themold; and injecting a pressurized molten resin, wherein, after theinjecting, there is a gap filled with the resin between a side wall ofthe mold and an outer surface of at least a first portion of the upper,wherein the gap is essentially zero at a contacting point, wherein thegap increases gradually from the contacting point in at least a firstregion of the mold.

In any of various embodiments described herein, the side wall of themold has a substantially convex shape.

In any of various embodiments described herein, the material of theupper is compressed by a first compression distance in a first part ofthe upper and a second compression distance in a second part of theupper, wherein the first compression distance is smaller than the secondcompression distance, wherein the first part of the upper is arranged ina heel or a toe region and the second part of the upper is arranged in alateral or a medial region of the upper.

In any of various embodiments described herein, the mold comprises atleast a first part and a second part, and wherein the first part and thesecond part are joining in a heel region and a toe region.

In any of various embodiments described herein, wherein the mold furthercomprises at least a first injection channel for injecting thepressurized molten resin, and wherein the first injection channel isarranged in a heel region of the mold.

In any of various embodiments described herein, the mold furthercomprises at least a second injection channel

In any of various embodiments described herein, the upper iswarp-knitted or weft-knitted

In any of various embodiments described herein, the method furthercomprises at least partially filling at least one knit-opening in thewarp-knitted or weft-knitted upper with the resin.

In any of various embodiments described herein, the resin forms at leasta part of a sole element of the article of footwear, wherein the soleelement is a midsole of the article of footwear.

In any of various embodiments described herein, the resin forms at leasta part of a sole element of the article of footwear, wherein the soleelement is the entire sole of the article of footwear.

Some embodiments described herein relate to a mold for producing anarticle of footwear comprising a side wall forming a cavity forreceiving a shoe upper, wherein the side wall is configured to contactthe upper at a contacting point and wherein, after injecting apressurized molten resin into the mold, there is a gap filled with theresin between a side wall of the mold and an outer surface of the upper,wherein the gap is essentially zero at the contacting point, wherein thegap increases gradually from the contacting point, in at least a firstregion of the mold; and at least a first injection channel for injectinga pressurized molten resin.

In any of various embodiments described herein, the mold furthercomprising at least a second injection channel.

Some embodiments described herein relate to an article of footwearcomprising: an upper; an injection-molded region comprising a resin, aninjection-molded region comprising a resin, wherein the resin coatingceases at a first position, and wherein a thickness of the resin coatingincreases gradually, in at least a first region of the upper.

In any of various embodiments described herein, the resin forms a soleelement of the article of footwear.

In any of various embodiments described herein, the resin forms a soleelement of the article of footwear, wherein the sole element is amidsole of the article of footwear.

In any of various embodiments described herein, the resin forms a soleelement of the article of footwear, wherein the sole element is theentire sole of the article of footwear.

In any of various embodiments described herein, wherein theinjection-molded region is devoid of any pinching.

REFERENCE SIGNS

-   -   10: article of footwear    -   11: upper    -   12: coating    -   13: sole element    -   14: channel    -   15: tongue    -   16: outsole    -   17: outer surface of the upper    -   18: surface of the coating    -   19: first region of the upper    -   20: first position    -   21: mold    -   22: gap    -   23: injection channel    -   24: intersection point    -   25: side wall    -   26: floor    -   27 a: first part    -   27 b: second part    -   28: loop    -   29: course direction    -   30: wale direction    -   31: mold as known in the art    -   34: intersection point for mold as known in the art    -   35: undercut    -   36: sideways direction    -   37: fourth portion    -   38: fifth portion    -   39: first region of the mold    -   40: lateral direction    -   41: uncompressed outer surface of upper    -   42: compressed outer surface of upper    -   43: last    -   44: toe region    -   45: heel region    -   46: medial region    -   47: lateral region    -   48: first compression distance    -   49: second compression distance    -   50: conventional shoe    -   51: conventional upper    -   52: pinching    -   53: conventional sole    -   54: flashing    -   61: knit-opening    -   62: rib    -   63: coated rib    -   64: coated knit-opening    -   65: edge

1. A method of producing an article of footwear comprising: providing anupper; providing a mold and opening the mold; inserting the upper intothe open mold; closing the mold; and injecting a pressurized moltenresin, wherein, after the injecting, there is a gap filled with theresin between a side wall of the mold and an outer surface of at least afirst portion of the upper, wherein the gap is essentially zero at acontacting point, wherein the gap increases gradually from thecontacting point in at least a first region of the mold.
 2. The methodaccording to claim 1, wherein the gap increases by less than 1 mm per mmof a distance from the contacting point in at least the first region ofthe mold, wherein the distance is measured along the outer surface ofthe upper.
 3. The method according to claim 1, wherein the side wallcontacts the outer surface at the contacting point at an angle of lessthan 30 degrees.
 4. The method according to claim 1, wherein the firstregion of the mold is arranged within 5 mm below the contacting point.5. The method according to claim 1, wherein closing the mold causes atleast a second portion of the upper to be compressed, and wherein thematerial of the upper is compressed by a first compression distance in afirst part of the upper and a second compression distance in a secondpart of the upper, wherein the first compression distance is smallerthan the second compression distance
 6. The method according to claim 1,wherein injecting a pressurized molten resin effects a furthercompression of at least a third portion of the upper, and wherein thefurther compression of at least the third portion of the upper causesthe gap to open between an outer surface of the upper and the side wallof the mold.
 7. The method according to claim 1, wherein the upper isarranged on a shoe last, prior to inserting the upper into the openmold.
 8. The method according to claim 1, wherein the resin forms atleast a part of a sole element of the article of footwear.
 9. A mold forproducing an article of footwear comprising: a side wall forming acavity for receiving a shoe upper, wherein the side wall is configuredto contact the upper at a contacting point and wherein, after injectinga pressurized molten resin into the mold, there is a gap filled with theresin between a side wall of the mold and an outer surface of the upper,wherein the gap is essentially zero at the contacting point, wherein thegap increases gradually from the contacting point, in at least a firstregion of the mold; and at least a first injection channel for injectinga pressurized molten resin.
 10. The mold according to claim 9, whereinthe gap increases by less than 1 mm per mm of a distance from thecontacting point in at least the first region of the mold, wherein thedistance is measured along the outer surface of the upper.
 11. The moldaccording to claim 9, wherein the first region of the mold is arrangedat least 2 cm above a floor of the cavity.
 12. The mold according toclaim 9, wherein the side wall of the mold has a substantially convexshape.
 13. The mold according to claim 9, wherein the mold comprises atleast a first part and a second part, and wherein the first part and thesecond part are joined in a heel and a toe region.
 14. An article offootwear, comprising: an upper; an injection-molded region comprising aresin, wherein the resin at least partly coats an outer surface of theupper, wherein the resin coating ceases at a first position, and whereina thickness of the resin coating increases gradually, in at least afirst region of the upper.
 15. The article of footwear according toclaim 14, wherein the thickness of the resin coating increases by lessthan 1 mm per mm of a distance from the first position in at least thefirst region of the upper, wherein the distance is measured along theouter surface of the upper.
 16. The article of footwear according toclaim 15, wherein the outer surface of the resin coating forms an angleof less than 45 degrees with an outer surface of the upper at the firstposition.
 17. The article of footwear according to claim 14, wherein thefirst region of the upper is arranged less than 5 mm below thecontacting point.
 18. The article of footwear according to claim 14,wherein the upper is warp-knitted or weft-knitted.
 19. The article offootwear according to claim 18, wherein at least one knit-opening in thewarp-knitted or weft-knitted upper is at least partially filled with theresin.
 20. The article of footwear according to claim 14, wherein anedge of the coating is flush with the outer surface of the upper.